In textile machines which process yarn, it is often necessary to grasp a free end of the yarn at a first location and to convey this free end of yarn to another desired second location in the textile machine. This is particularly true in the case of a two-for-one twister textile yarn processing machine and other yarn processing machines having yarn processing stations mounted in generally side-by-side relationship along the outside of the machine and each having a spindle assembly carrying a supply package of yarn for processing of the yarn during passage through the spindle assembly and a processed yarn take-up assembly positioned generally axially above each of the spindle assemblies for receiving the processed yarn therefrom and for forming a take-up package of processed yarn, wherein the yarn must be grasped from the spindle assembly and conveyed to the take-up assembly during threading-up of each yarn processing station following doffing of a full package of processed yarn or the breakage of yarn during yarn processing.
In the case of such two-for-one twister textile yarn processing machines, the spindle assemblies each include a driven rotating rotor mechanism, a stationary carrier mechanism for carrying a hollow supply package of yarn and having a basket device surrounding the supply package, a balloon limitor device surrounding the basket device and providing a space therebetween, and an elongate yarn passageway extending downwardly through the top of the carrier mechanism along the axis of the spindle assembly and radially outwardly through the rotor mechanism into the space between the basket device and the balloon limitor for the passage of yarn from the supply package downwardly and outwardly through the passageway and upwardly through the space between the balloon limitor and basket device during yarn processing. From the spindle assembly, the yarn passes through the take-up assembly which conventionally includes a yarn guide eyelet, a pre-take-up roll, a yarn traversing mechanism and a yarn take-up or package roll device including a cradle mechanism having centering discs for carrying a surface-driven take-up yarn bobbin therebetween for the winding of processed yarn thereon through surface engagement with a driven friction drive roll.
Some of these two-for-one twister textile yarn processing machines are provided with automatic threading mechanisms particularly for the spindle assembly portions of the yarn processing stations, such as the pneumatic threading mechanisms disclosed in U.S. Pat. No. 3,731,478 issued May 8, 1973 and U.S. Pat. No. 3,975,873, issued Aug. 24, 1976, both of which are assigned to the assignee of the present invention.
As may be seen in these U.S. patents, pneumatic threading mechanisms are provided for automatically threading yarn withdrawn from the supply package through the yarn passageway of the spindle assembly and through the space provided between the balloon limitor and the basket device by creating a suction through the yarn entry portion of the spindle assembly passageway and a positive air stream through the yarn exit portion of the passageway and through the space between the balloon limitor and basket device. However, the yarn must then be grasped as it emerges upwardly from the space between the balloon limitor and the basket device of the spindle assembly and conveyed to the take-up bobbin in the take-up assembly. This may be accomplished either manually or automatically.
In this regard, assignee's U.S. Pat. No. 3,731,478 discloses further threading devices in the form of an air injector nozzle disposed over the gap between the balloon limitor and basket device of the spindle assembly for capturing the yarn propelled upwardly through this space so that the yarn may be passed through the thread guide eyelet associated with the take-up assembly. After the yarn has passed through this thread guide eyelet, the yarn must be manually conveyed over the remaining elements of the take-up assembly and applied to the take-up bobbin. In an additional embodiment of these further threading devices of assignee's U.S. Pat. No. 3,731,478 there is disclosed the use of deflection members in connection with the injector nozzle for deflecting the yarn upwardly toward the take-up bobbin so that operator need only grasp the yarn at the location of the take-up bobbin and apply the yarn to the take-up bobbin during threading-up of the yarn processing station.
However, with all the above-described mechanisms and with all of the automatic threading mechanisms for yarn processing stations of textile machines presently known, some manual labor by an operator is required in the threading-up of the yarn from the spindle assembly to the take-up assembly or from a first location in the textile machine to a desired second location in the textile machine.